some details based on #1221

This new version adds:
- fsdb waveforms
- simv.db.dir/ directory for VHDL top configs
- ucli.key
- vc_hdrs.h
- Also added a few comments about where each one of the files come from.

JetBrains recently released a new C/C++ IDE: CLion

.ensime_cache is cache dir.

In addition to `.Spotlight-V100` and `.Trashes`, the following dotfiles
may appear at the root of all OSX volumes (not just external disks):

- `.DocumentRevisions-V100`: auto-save and versions storage
- `.fseventsd`: file system event storage
- `.Temporaryitems`: temp directory used by some applications instead of
                     /tmp and /var/tmp
- `.VolumeIcon.icns`: storage of custom icon for volume, if set

http://wiki.freepascal.org/File_extensions

Whether to use VCS or any other simulator is a choice of the individual designer rather than of the project as a whole.

template

Ignores all .rdb files, (default: dump.rdb).

These files contain a binary representation of the in-memory
redis data that is generated using cli tools or on a redis
failure.

They can be used to restore a redis db, and may contain
sensitive data so should not be saved in version control.

Continuation of https://github.com/github/gitignore/pull/594/ and details from http://support.microsoft.com/kb/211632

Intellij's iml file can be anywhere on the path.
This is true for multi-module maven project where each module has its own $projectName.iml file in its own directory.

These are relatively new, the crashlytics.properties file contains the secret and can [alternatively](https://plus.google.com/+AntonioBertucci/posts/S9krjvXfgfm) contain the apikey to rid your repo of the extra strings file.

The .settings folder contains all of the user-specific preferences for Momentics (like it does for Eclipse, since they're the same underneath). Should be local only.

This .gitignore now ignores everything that build clean gets rid of

As described on https://docs.python.org/dev/library/venv.html#creating-virtual-environments

The template hasn't been touched since it was added to this collection.
There are some problems with it - mainly that it's hard to know if these
rules are all still relevant, and the large prose block is probably more
confusing than helpful here.